I will buy a Mesa 7i77 card Europe

Does that mean you already have a Mesa 5i25 or 6i25 or 7i92 or any other FPGA card?
If yes, then look for Mesa 7i85 and 7i83, the first has 4 encoders and 4 or 5 Smart Serial ports, one of these serial ports is used to wire the 7i83 that has analog outputs for +-10V, so that makes a 7i77.
In Portugal:
eusurplus.com/index.php?route=product/pr...ct_id=61&search=7i83
in stock
eusurplus.com/index.php?route=product/pr...t_id=105&search=7i85
in stock
OR
eusurplus.com/index.php?route=product/pr...ct_id=54&search=7i85

In Germany:
www.welectron.com/Mesa-Electronics-7i85-...S-422-Daughtercard_1
out of stock
OR
www.welectron.com/Mesa-Electronics-7i85S...ntial-Daughtercard_1
out of stock
www.welectron.com/Mesa-Electronics-7i83-...ut-Servo-Interface_1
out of stock